360 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxn. 



hog is said to be fond of them. Birds prey somewhat extensively 

 upon them, the hawk, crow, ptarmigan, hirk, grouse, gull, and 

 ])]ackbird ])eing among those credited with eating them, A large toad 

 has been reported as following creeks to feed upon the drowned 

 specimens, while fish have been recorded as gorging themselves on the 

 drowned crickets. No insect enemies are known, but specimens have 

 been found infested internally with hair-worms. A large wasp, 

 Palmodes inoris Kohl, preys upon the allied Peranahrun scabricoUis 

 and ma}^ also attack this insect, though no record of its doing so has 

 yet appeared. Red mites have been recorded as occurring on the 

 Anahrus. 



When vast hordes of Anah7'u,}< appear, laying waste large areas of 

 cultivated fields, they form a scourge not easily combatted. Ever}"- 

 thing in their line of march falls before their ravenous appetites. 

 Bodies of water of considerable size are bridged b}^ the thousands of 

 the drowned and across march the millions. Armies of the advanc- 

 ing hordes often extend over a mile, the ground over which they 

 move being literally covered by the slowl}' moving mass. . The rate of 

 travel is probably little more than one-half mile a day, though it has 

 been recorded as twice that much. Since the earliest settlements the 

 ranches of the arid west have suii'ered from the ravages of these insects, 

 and portions of Idaho and neighboring States seem to suffer more or 

 less nearly every year. 



A number of remedies against this pest have been tried and recom- 

 mended. The papers of Doten, Aldrich, and Gillette, above mentioned, 

 should be read for information regarding various remedies. Herding 

 the ami}" off' cultivated fields, fencing them out b}^ means of vertical 

 walls of tin, wood, oil-cloth or other material, killing the insects by 

 poisons, trampling b}' sheep, crushing with rollers, trapping in 

 vertical-sided trenches, and killing with oil have all been considered. 

 The effectiveness of oil in killing the pests is a matter of some dispute. 

 It seems as if the insects are able to resist quite thorough applications 

 of even pure kerosene, recovering, according to Professor Gillette, 

 after a moderate spraying, but dying when immersed in it. Poisons 

 act too slowly to be of practical value in times of invasion. Herding 

 and fencing are probably the best methods of warding off' their attacks. 

 The suggestion has been made of innoculating migrating hordes with 

 fungus disease, but the dryness of the climate of the infested regions 

 would scarcely favor the success of such experiments. 



The insect figured by Woodworth in Bulletin No. 149 of the California 

 Experiment Station, fig. 8/^, as A. KhipJex is certainly not this species, 

 but some long-legged dectician, probably a species of the genus 

 Cacopteris. 



